Azo dyes



Patented July 4, 1939 UNITED STATES '1; r 2,164,785 AZO DYES ware No Drawing.

19 Claims;

This invention relates to azo dyes. Morepar ticularly this invention deals with a novel" series of Fpolyazo dyes whichtare characterized, by the general formula A Ri-N=N-R#-CONH-A1k1.NHCOR-N V V w t I ZAP-"R2, wherein Alk designates the bivalent residue of a saturated hydrocarbon, for instance the residue of a paraffin or cycloparaflin hydrocarbon; R is a diyalent aryl radical of the benzene series, for

" instance benzene or its alkyL'alkoxy or halogen derivatives; while R1 and R2 are any azo dye coupling components whatsoever, which may or may not containfurther azo groups. Depending on whetherRi and R2 do not contain. or do contain further azo bridges, the novel dyes of my invention are disazo, trisazo, or tetrakisazo corn-W pounds. The -N=N groups must be meta or para to the CONH groups on the divalent aryl rad c s Y U.

' ,Itisan object of my invention to provide new azddyes which are useful for dyeing vegetable,

animal or synthetic fibers. It is a further object of my invention to provide 'new azo 'dyes which utilize as initial materials the novel diamino intermediates of copending application Serial No. 1 61,Q39, filed by myself and CarltonWrCroco, on

30 August 26, 1937. These intermediates are char acterized by the generalformula I I H2N--R CONI-I--Alk -NHCOTR-NH2,-

wherein R is aphenylene radical which may be substituted by 'alkyl, alkoxy or halogen groups,

while Alk is a parafi'ln hydrocarbon having from 2 to 18carbon atoms in itsstructurQQr a cyclo- ,parafildhydrocarbon. Other useful objects of this' invention. will appear as the description proceeds. I y 7 40 1 I haveifound that azo dyestuffsof the above general formula are characterized by dyeing fiber by the direct method in bright, commercially dcsirable shades of color, and the, dyeingsgenerally possess good fastness qualities; The e ractshade depends on the choice of component. Furthermore, by proper choice of component dyes may be produced which have afiinity for cotton and regenerated cellulose, wool or silk, or cellulose ester or ether materials.

The mode of procedure in preparing the novel dyestuffs of my invention, generally comprises of the general formula PATENT OFFICE ADDlicatiomNovember 20,1931, Serial N0. 175,640

wherein R and Alk have the same significance as above, and coupling to two moles of a suitable coupling component, depending on what type of fiber the color is desired for,'or' on the shade desired, This choice of component per se follows 5 well established 1ules, wl1ich are known in the art For instance, if 'a dye for cellulose acetate material is desired, a coupling component free of water solubilizing groups is selected; for instance, cresidine, m-toluidine, or l-phenyl-3-methyl-5- 10 pyrazolone, If a dye for cotton is desired, a component having water-solubilizing groups, namely sulfa or carboxy, isselected, for instance, J-acid or m-arnino phenyl-pyrazolone-carboxylic acid.

If the coupling component contains amino 15 groupsthe dyestuff may be further developed on the fiber, by *tetra'zotizing' and coupling to a suitable developer, such as beta-naphthol, phenylmethyl-pyrazolone, or meta-tolylene diamine. This "type of coupling component and procedure 20 is particularly desirable in the cases of dyes designed for use on vegetable fiber.

The tetraaoti'z'edintermediate aforementioned" may-also be coupled 'in two steps using difierent' components in: each stepilrnole of each), there- 25 by producing an unsymmetrical disazo compound. If in this case one of thecompon'entschosen is it-" selff an a zo compound, the resulting dyestuff will be atrisazo"comp un But the tetrazotized intermediate mayalso'bejcoupfledin one step to two moles of as am compound," thereby produce inga tetrakisazo dye in substance."

The actualdetails of procedure may follow in each case the 'nor'mal procedure preferred with each particular coupling component, as is well known tfo tho seskilled 'i'n'ftheart, 1

The preparation of the novel di'amino com;- pounds which serveas' initial materials for'm'y inventionis described incopending application, Serial No, 161,039, fi1ed by myselfand Carlton 40 W. Croce, on August 26, 1937. Generally speak ing, a nitrobenzoyl chloride; such as nitiro-benzbyl chloride itself or' analkoxy, alkyl or halogen dek rivative thereof, is condensed with a diamine of a saturated hydrocarbon'fof the general formula H2NA1k-NH2, whereinAllistahds for the bivalent residue of a 'paraflin hydrocarbon" having fro-m g to ls'carbon atoms in its structure, or for'the residue of a cycloparaffin, such as cyclohexane ora l'iorriolog thereof. The condensation is generally effected in aqueous medium, in the presence of acid absorbing agents, and results in a dinitro compound of the general formula as. p

l 600 parts of water.

wherein R and Alk have the same significance as above. The N02 groups must be meta or para to the CONH groups on the divalent radicals, R. By reduction in the 'usual manner, for instanceata yt hyd a n, the desired diamino comp ounds are obtained.

typical c'oinpounds of the above type, which may serve as initial materials for my present invention, the following diamino compounds may he mentiqnfld:

N, N =c li (peaminobenzoyl) -1,2-ethylene-diamine;t

l l ,l l'-di(m aminobenzoyl) 1,10 decylene diamlne;

N,N'-di (p-aminobenzoyl) -1,4-diamino-cyclohexane;

N ,N'-di(maminobenzoyl) -1,6-hexylenediamine N,N'-di(4-methoxy-3-aminobenzoyl) 1,2 -ethyl.-

enediamine;

The disazo compound thus produced dyes cotton by the direchmethod in. orange shades. When developed on the fiber by tetrazotization and coupling to betarnaphtliol, it produces a bright orange dyeing of? outstanding fastness to washing.

Example II Tetrazotize 1419' parts of di-(p-aminobenzoyl) ethylene-diamine following the directions given in Example I- Add 15.2 parts of salicylic acid to 500 parts water. Stir the mixture for an hour. Add caustic soda (approximately 0.11 mole part) until the solid particles are completely dissolved leaving the :solution of such alkalinity that it will give a .red or orange coloration when applied to brilliant :yellow paper. Add 200 parts of 10% soda ash solution, and stir until it is dissolved (approximately 20 minutes). Adjust the temperature to 20 C., if necessary. Slowly add the tetrazo of di- (p-aminobenzoyl)-ethylene-diamine to the rapidly agitated solution of salicylic acid during approximately one-half hour. Stir 4 hours allowing the temperature of the mass to rise to 20 to 25 C. Slowly heat the mixture to 75 C. over a period of one hour.

Add approximately 195 parts.

of salt (15% by volume) and stir one-half hour..

The dye should show practically no bleed out.

"when spotted on filter paper. Filter and dry the wet press cake in an oven at 80 to 90 C. The dried powder is yellow in appearance. It dissolves in water giving a yellow solution.

The probable formula of the dye is:

absorbed. Keep a very slight. excess of nitrite.- for 20 minutes at 10 to 12 C;

Stir 39.5 parts of p-aminobenzoyl-J-acid into.- slowl add just enough am monium hydroxideto dissolve the P-amino ben zoyl-J-acid (approximately 9 parts of 27%) leaving the solution slightly alkaline to brilliantyellow paper. Add 34 parts of soda ash, stir until dissolved (approximately 10 minutes) and cool. to 10?- C.- by the addition of ice. Slowly add the: tetrazo solution prepared above to the p-amino-- benzoyl-J-acid solution, maintaining good agita-- tion. Stir 3 hours allowing the mass to gradually volume) of salt. Stir 20 minutes.

come to room temperature, maintaining an alkalinity which will give a strong red coloration. on brilliant yellow paper, and an excess of p-- aminobenzoyl-Jacid. Slowly warm the mass to C. and add approximately 180 parts (10% by Filter the: coupling mass, and dry the press cake in an oven. at to C. When powdered the dry product is reddish orange in appearance. It dissolves in water to give an orange solution.

Its probable structural formula is:

S OaNa i C OzNB.

The compound thus; produced dyes wool from acid a n. yellow shades. When chromed on the fiber, in. the usual manner, it produces a yellow shade of good fastness qualities.

Example I I I solution to 30 C. Add the solution of cresidine to the tetrazo solution of di-(p-aminobenzoyD- ethylene-diamine during approximately five minutes. Immediately add 22 parts of sodium acetate. Maintain a neutral acidity on Congo .red paper and an excess of cresidine. Stir 12 hours. Slowly warm the reaction mixture to 60 C. Filter and dry the wet press cake at 80 to 90 C. The dry powder is yellow in appearance, and quite insoluble in water. It dissolves in alco- 1101, giving a yellow solution.

SOaNa rnNOc ONE Its probable formula is:

smooth slurry is obtained (approximately 1 hour).

The product thus produced dyes cellulose acetate material to a yellow shade of good fastness qualities.

Example IV Tetrazotize 14.9 parts of di-(p-aminobenzoyl) ethylene-diamine per directions in Example I listed above. Cool the tetrazo to 0 C.

Add 17.9 parts of p-aminobenzoyl-J-acid to 200 parts of water. Stir the mixture for approximately one hour. Slowly add ammonia (approximately 4 parts of 27% solution) until the solid material is completely dissolved leaving the solution only very slightly alkaline as shown by its giving an orange-red color when spotted on brilliant yellow paper. Add 18 parts of soda ash, stir until it is dissolved (approximately 20 minutes), and cool to'0 C.

Add the solution of p-aminobenzoyl-J-acid very rapidly to the tetrazo solution above prepared. Add soda ash, as necessary to maintain distinct alkalinity on brilliant yellow paper (approximately 1 or 2 parts). As soon as the test for tetrazo is negative as shown by getting no color reaction when an alkaline I-I-acid solution is streaked across a rim of the solution mass on fspot" paper, immediately add the entire mass to the following alkaline solution of l-meta-aminopheny1-5-pyrazolone-3-carboxylic acid, keeping the temperature'at 0 C.

Stir 24 parts of 1-meta-amino-phenyl-5-pyrazolone-B-carboxylic acid with 300 parts of water. Add approximately 7 parts of soda ash, until the solid material is completely dissolved to a clear solution, which shows an orange red color when spotted on brilliant yellow paper. Add 10 parts of soda ash and cool the solution to 0 0.

Stir for 4 hours after adding the above diazo to the solution of 1-meta-amino-phenyl-5-pyrazolone' 3-carboxylic acid, allowing the temperature to rise and maintaining an excess of coupling component. Add more soda ash, if necessary, in order to maintain an immediate red color when the reaction mass is spotted in brilliant yellow paper. approximately 170 parts of salt (10% by volume).

Filter and dry the press cake in an oven at to 100 C. The dried product is reddish-orange in appearance, and dissolves in water to give a yellow-orange solution. The probable structure of the dye is SOaNa Example V Stir 3'? parts of p-nitraniline with 2000 parts of water and 26 parts of hydrochloric acid until a solution as rapidly as possible.

Warm slowly the mass to 75 C., and add Add ice to lower the temperature to 10 C., and then 19 parts of sodium nitrite as a Z-normal Continue the diazotization for one hour, maintaining an excess of nitrite as shown by a spot turning potassium iodide starch paper blue.

To a slurry of parts of H-acid in 1000 parts of water, add 10 parts (.025 mole) of sodium hydroxide as a 2-normal solution leaving the solution slightly acid to litmus paper. Cool the solution to 0 C. before coupling by adding ice as necessary.

The solution of H-acid was run slowly (over approximately one-half hour) into the paranitraniline diazoprepared above. The combination was stirred overnight. Next morning the solution was made slightly alkaline to brilliant yellow paper by addition of 74 parts of sodium carbonate.

75 parts of di(para-amino-benzoyl) ethylene diamine was dissolved in 2000 parts of water by the use of 46 parts of hydrochloric acid. The solution was iced to 10 C. and 35 parts of sodium nitrite as 2-normal solution was added as rapidly as absorbed (approximately 5 minutes). A slight excess nitrite was maintained for 15 minutes.

A solution of salicylic acid was prepared by stirring 35 parts of the acid with 200 parts of water. Caustic soda (approximately 10. parts) was added until the salicylic acid was completely dissolved, leaving the solution slightly alkaline to brilliant yellow paper. 80 parts of sodium carbonate was added to the solution and enough ice to lower the temperature to 10 C.

The alkaline solutionof salicylic acid was run into the solution of the tetrazo prepared as above as rapidly as possible (approximately 2,

minutes). The coupling was balanced to slight excess of salicylic acid as indicated by testing with ferric chloride. Streaking the solution across a spot of ferric chloride solution caused the latter to turn dark. Stirring was continued for 1 hour.

The alkaline solution of the para-nitraniline I acid I-I-acid coupling was next run into the above salicylic acid benzidine diazo. Stirring was continued for 4 hours keeping the solution alkaline, as shown by a spot of it turning brilliant yellow paper a red color. More soda ash is added, if

necessary, to maintain the desired alkalinity.

The solution was heated slowli to'65 to 70and 57 600 parts of sodium chloride (approximately by weight) was added. The dye precipitated on hour stirring. The dye was filtered 01f and dried in an oven. It is soluble in water, giving a green solution which dyes cotton bluish green shades of good fastness to washing. Its probable formula is Stir until smooth slurry is obtained. Add 30 parts of 32% aqueous hydrochloric acid and adjust temperature to 15 C. by the addition of ice. Add '7 parts of sodium nitrite as 30% solution and stir 1 hours, maintaining an excess of nitrite by subsequent additions if necessary, as shown by its giving a blue spot when streaked on potassium NaOgS- s 031% I OflN N=N -N=N CONHCHzGHaNHCO NH: OH

N II N l COzNa Example VI iodide starch paper, and acidity such that it gives a blue spot on Congo red paper by further addi- The dye p-nitraniline i H-acid benzidine phenol was prepared by the above procedure by the substitution of phenol for salicylic acid. A green dye was obtained, which had good affinity for cotton or regenerated cellulose.

Example VII Slurry 14.9 parts of di-(m-amino-benzoyl) ethylene diamine with 400 parts of water. Add 25 parts of 32% aqueous hydrochloric acid. Stir until completely dissolved and cool to C. Add '7 parts of sodium nitrite as 30% solution as rapidly as absorbed. Keep a slight excess of nitrite by slight addition if necessary, for 20 minutes at 10 to 12 C'., as shown by a spot of the solution giving a blue spot on potassium iodide starch paper.

Slurry 25 parts of J-acid with 600 parts of water. Add 11 parts of soda ash and stir until the J -acid is completely dissolved. Add 32 parts of soda ash just before coupling, and cool to 0 C. by the addition of ice. Slowly (approximately 15 minutes) add the tetrazo solution prepared above to the J -acid solution maintaining good agitation. Maintain distinct alkalinity on brilliant yellow paper and an excess of J -acid by the respective addition of soda ash or J -acid as necessary. Stir 1 hour. Slowly warm the dye to 75 C. and add approximately 180 parts of salt (10% by volume). Stir minutes. Filter the salted dye'and re.- slurry the press cake with 600 parts of water.

tion of hydrochloric acid, if necessary.

Slurry 31.5 parts of phenyl J-acid with 600 parts of water. Add 40 parts of soda ash and stir until the phenyl J -acid is dissolved. Adjust the temperature to 15 C. by adding ice and slowly run in the tetrazo prepared above, maintaining strong soda ash alkalinity as shown by spotting on brilliant yellow paper by subsequent addition of soda ash if necessary. Keep an excess of phenyl J -acid, by the addition of small amounts, if necessary. Stir 2 hours. Slowly warm the tetrakisazo dye to 75 C. and add approximately 200 parts of salt (10% by volume). Filter the salted dye and dry the press cake in an oven, at 80 to 90 C. The probable structural formula of the product is:

N NaOaS- It dissolves in water to give a bordeaux solution, which has good affinity for cotton or regenerated cellulose.

Example VIII and tetrakisazo dyes may likewise be prepared,

following in general the mode of (procedure nor.-

mallyused; in therart for synthesis -oi analogous dyes from diamino commu ida The. following is alistof" some of" the dyesactually prepared byus; together with the colors producedtby them on. the;,fibers;r espective1y indi:

cated, as well as the; color obtained' y dfivelopa ment: on the. fiber, where; feasible, with beta naphtholl. In: this, tabla the symbol PAB stands for the words:paraaminoben qy an he ymb l areyhydroxy r. aminoderivatives of benzene,

naphthalene. and other and nuclei. "'Amongothei" typeslf'of products'that can be used as couplingquinoline.

The two coupling components, usually used per moleof diazo component, may consist of like or unlike intermediates. Thelatter need. not neces- MAB: for'metaammobenzoyl sarily be used in equi-molecular proportions.

Dyesespecially usefulfor cottonor regenerated cellulose Shade when D t (glila'zgigzed 3 lrec e er an Tetrazgroi Coupledtotwomolesoi shade developed I with beta naphth'ol Di (PAB)-deca-methylene diamine.-- 2-angino--naphthol-7-sulionic acid; (J- acid)-. Bordeaux.

Do 1-n1eta-amino phenyl--pYrazolone-S-carboxyhcacid; Orange. Do cid Do. D Do. Do

D0 Red Red. Di(MAB)-decamethylene diamine.-. Orange-.. Orange. Do; Ye11ow D0. D1 (PAB) -ethylene diamine Red Bordeaux. Do 0range 0range.--

Do. Do. y One rnoleof l-nietaeam o-phen }Orange Red brown.

carboxylic acid? One mole of salicylic acid Brown One mole of gamma acid; o Di(1 AB)-3E5 diamino'benzoyl-J-acid. Orange." Orange. Di(MAB)-ethylene diamme- J-acid Re Bordeaux Do (MAB)-J-ac1d Orange Orange.'- Do- PAB)- J-acid do Do. Do l-meta-a Yellow Do. Di(PAB)-eyclohexy1-d1amine .T-acid. Red Bordeaux D0- H P.A B)-J-aci d Oran e Orange. Do 1-meta-arnin' o'-pl1en l-5-py'razoloned-carbogrylic acid. Yellow Do. D .(MAlEl-l-amd I a I Orange--- Do.

Wool dyes Tetrazo of- Coupled totwo moles .of- Shade Di(PAB)decamethy1ene diamine (z-fi-diehlorv i-suliophenyl)-3-methy1-5-pyrazo1one .Yellow. Di(MA=B)decamet-hylene dia1u 0 Do. Di(PAB)eth lene 'diamine. 1(2-5-d10111or-e-sulfophenyl)-3-1netl1ylpyrazolone;; -Do. D0 g l-aqetylaguinofirhydroxyn phthalene-3-6-disulfonic,ac1d. Orange Do.-- H-acid. Violet.

Sali yli Ad Yellow when chromed on ,the fiber.

'time: ar lezeeei 1 8-dihydr oiry naphthalenee'ri. Orange. Dyes which have a fimfty for cellulose acetate v flfetrazo oi- Coupled to two moles h j j gs j Di(PAB)ethylene'diamine. Q lamino-2-methoxy-5-methyl benzene Metaitoluidine 'ResorcinoLflll.

Other: dyes .thanthose nentioned in the aboye table,-may' likewise be prepared psing the tetrazo compounds. of the above mentioned diamines of the general "formula any p u abl eo zeqllnlm derivatives. z'I- hegNlgIz groups rnust be; ;1 neta..or para to the CONH groups on the divalent aryl radicals-7R; asinceif they are-ling the ortho posifi'on,' "the*compound will undergo ring closure instead of coupling. Most of such compounds "Qthersubstituent groups, such as halogen, alkyl, alkoxylaryl, aralkyl; substituted amino, azo, earh ixy, carbonyl and sulfonic acid; may be present as 'substituentyg'roups on the coupling corriponent, as long as they do not block the coupling.

direct and developed dyeing of cotton." Theide- [iii 6 veloped dyeings, using beta naphthol as the developing agent, have outstanding fastness to washing. Chromed wool dyeings of excellent properties have also been made.

The following additional examples illustrate the application of my novel dyestuffs to the various fibers, such as cotton, wool or cellulose acetate. The first of these illustrates further the development of the dye on the fiber.

Example IX--Dyeing of cotton Five parts of cotton piece goods is dyed by immersion into a solution of ten-hundredths parts of the disazodye obtained by coupling tetbeing slowly added to exhaust the dyestuff. The

dyed fabric is rinsed in cold water and put in 200 parts of water at 20 0. Add three-tenths parts of sodium nitrite and four-tenths parts of sulfuric acid. Stir 15 minutes. Rinse with cold water. Dissolve one-tenth part of beta-naphthol in 200 parts water and one-twentieth part of caustic soda. Stir the solution rapidly while adding the above rinsed piece goods. Stir 15 minutes. Rinse in cold Water and dry. The dyeing is a bright orange shade of outstanding fastness to washing. I 7

Example XDyezng of wool Dissolve one tenth part of dyestuff, phenylgamma acid di (PAB) ethylene-diamine sa1icylic acid, in 25 parts of Water at 160 to 170 F. Add 5 parts of 10% solution of Glaubers salt, followed by 1 parts of 10% acetic acid solution. Heat to 160 to 170 Add 5 parts of wool material o-r skein. Heat the solution to the boiling point of the water and maintain this temperature for A hour, adding water as necessary to keep it equal to the original volume. Add 1%.; parts more of 10% acetic acid solution, and keep the dyebath at the boil for 15 minutes longer, adding water as necessary to keep the original concentration. Remove the wool goods, rinse in cold water, and dry in an oven at 'to C. The dyed fabric is a nice brown shade with excellent fastness to fulling.

Example XI-Dyeing of cellulose acetate Add 0.10 part of the .dyestuif, cresidine di (PAB) ethylene diamine cresidine, to 1 part of 10% olive oil soap solution and paste the slurry until thoroughly mixed. Slowly add while constantly stirring, 200 parts of warm water at to F. Put in 5 parts of Acele, either as skein or piece goods. Stir at regular intervals during 40 minutes, keeping the temperature at to F. Remove the Acele from the solution, rinse in cold water, and dry in an oven at 90 to 100 C. The dyed fabric is orange in shade.

I claim:

1. A disazo dye having the general formula wherein Alk designates the bivalent residue of a saturated hydrocarbon having from 2 to 18 carbon atoms in its structure, R is divalent radical of the benzene series, the -N=:N- groups are meta or para to the CONH groups, and R1 and R2 designate azo dye coupling components.

2. A disazo dye having the general formula wherein Alk designates the bivalent residue of a saturated hydrocarbon having from 2 to 18 carbon atoms in its structure, the N=N groups are mete. or para to the CONH groups, and R1 and R2 designate azo dye coupling components.

3. A disazo dye having the general formula wherein Alk designates the bivalent residue of a saturated hydrocarbon having from 2 to 18 carbon atoms in its structure, the -N=N'- groups are meta or para to the CONH groups, and R1 designates an azo dye coupling component containing a water-solubilizing radical.

4. A disazo dye having the general formula wherein Alk designates the bivalent residue of a saturated hydrocarbon having from 2 to 18 carbon atoms in its structure, the -N=N- groups are meta or para to the CONH groups, and R1 designates an azo dye coupling component containing a water-solubilizing radical and containing further a diazotizable amino group.

5. A disazo dye having the following general formula:

wherein Alk designates the bivalent residue of a saturated hydrocarbon having from 2 to 18 carbon atoms in its structure, the -N=N-- groups are meta or para to the CONH groups, and R1 designates an azo dye coupling component containing a sulfo water-solubilizing radical.

6. A disazo dye having the following formula wherein Alk designates the bivalent residue of a saturated hydrocarbon having from 2 to 18 carbon atoms in its structure, the -N=N groups are meta or para to the CONH groups, and R1 designates an azo dye coupling component free from water-solubilizing groups.

8. A disazo dye having the general formula wherein R1 and R2 designate azo dye coupling components, and the N==N groups are meta or para to the CONH groups.

9. A disazo dye having the general formula wherein R1 designates an azo dye coupling component containing a water-solubilizing radical, and the N=N groups are meta or para to the CONH groups.

10. A disazo dye having the general formula wherein R1 designates an azo dye coupling component containing a water-solubilizing radical and containing further a diazotizable amino group, and the N=N- groups are meta or para to the CONH groups.

11. A disazo dye having the general formula wherein R1 designates an azo dye coupling component free from water-solubilizing groups, and the-N=N groups are meta or para to the CONH groups. 7

12. A disazo dye having the general formula which comprises tetrazotizing a diamino compound of the general formula wherein Alk designates the bivalent residue of a saturated hydrocarbon having from 2 to 18 carbon atoms in its structure, the NHz groups being meta or para to the CONH groups, and coupling the tetrazo compound thus produced to two molecules of an azo dye coupling component.

17. The process of producing a disazo dye, which comprises tetrazotizing a diamino compound of the general formula the NHz groups being metaor para to the CONH groups, and coupling the tetrazo compound thus produced to two molecules of an azo dye coupling component containing a water-solubilizing radical.

18. The process of producing a disazo dye, which comprises tetrazotizing a diamino compound of the general formula wherein R1 designates the radical of an aminobenzoyl-J-acid.

13. A disazo dye having the general formula the NHz groups being meta or para to the CONH groups, and coupling the tetrazo compound thus produced to two molecules of an azo dye coupling wherein R1 designates the radical of sodium salicylate.

14. A disazo dye having the general formula component containing a water-solubillzing radical and containing further a diazotizable amino group.

wherein R1 designates the radical oi" resorcinol.

15. The process of producing a polyazo dye, which comprises tetrazotizing a diamino compound of the general formula 19. The process of producing a disazo dye, which comprises tetrazotizing a diamino compound of the general formula the NHz groups being meta or para to the CONH groups, and coupling the tetrazo compound thus produced to two molecules of an azo dye coupling component free from water-solubilizing groups.

SWANIE SIGUARD ROSSANDER. 

